Programmer tries to explain binary search to the police

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Just because they say 'no visual cue' does not mean that is no visual cue.

It literally, explicitly does, because they are talking about a hypothetical situation where no visual cues are left. If no visual cues are left, then there are no visual cues to see.

Why, because you say so? Yes, I can. Of course I can.

Okay. I should have been extremely specific. You cannot rightly and correctly say that there are visual cues that could be found when the other person explicitly says that there are no visual cues to be found, because in the hypothetical situation that they've brought up, there would be no visual cues to find, and so while you are physically capable of stating the phrase "just look for the visual cues," or some variation thereof, you are incorrect in the assumption that there would be visual cues to find.

When somebody says "you can't say" followed by a statement that's incorrect, they aren't trying to tell you that you are physically incapable of saying that statement; rather, there is an implicit "correctly" or "honestly" between the "can't" and "say."

because they are talking about a hypothetical situation where no visual cues are left.

No, I am not. I'm disagreeing with that, and my comments are stating as much. I'm allowed to disagree with what someone is saying.

You seem to talk about different things when you say "visual clue". Yes, there will be a small duration in the video where the event happens and maybe a short aftermath. That's not a visual clue, that's the thing you're looking for. What all others mean by visual clue is a definite indicator that you can see when picking any random frame in the video that tells you if that frame is before or after the event. That allows you to exclude all other frames from your search, reducing your search range by half.

A stolen bike, a broken window, your examples that trash the place or end up with a crowd of people in the area, all leave such a visual clue. At any random frame you can check if the bike is there or not, the window is broken or not, etc.

But let's say you have footage of the street facing CCTV and you need to find at what time the suspect left the scene (crime happened somewhere else). There's nothing that tells you when looking at the halfway point if the suspect already passed or didn't. You still have to look at both sides of that point in time.

The classic example for binary search is looking for a word in a dictionary. You open it halfway and see if the words there are before or after the one you're looking for. Then you know which half of the dictionary you need to look in next. Then you use the same method for that half and so on.

But what if someone highlighted a word in the dictionary and you don't know which word? Binary search is useless. You have to skim through the whole thing until you see it.

I believe what you stated is partially incorrect, as you don't look at just a single frame, you compare it to the frames before and after as well, you search for pattern changes.

I stand by what I said. I don't believe you're seeing the whole thing (pardon the pun).

Five months later, and I'm not going down this rabbit hole again. I'll just leave it at agree to disagree.

Even if you're looking at a range, it still won't tell you anything except that you found the guy or you didn't find the guy. If you didn't, what's the next step? (In the find when the suspect passed in front of the camera scenario)